Abstract: The invention relates to a braking and/or clamping device for a shaft guided in relation to a main body, comprising an actuation assembly and a shaft-coupling assembly. In this case, the actuation assembly comprises a split housing which has two bending plates which are elastically deformable in some regions. The bending plates each have tong jaws with friction surfaces, the respective surface normal of which are directed inwards. A sealed pressure chamber, which can be filled with a pressure medium, lies between the bending plates. Parts of a shaft-coupling assembly project between the clamping zones, said parts establishing the linking for the braked or clamped shaft. When the pressure in the pressure chamber is relieved, the frictional surfaces of the actuation assembly can be applied to the frictional surfaces of the shaft-coupling assembly, thereby producing the braking and/or clamping force.